The present invention relates to a chain tensioner for an endless chain, whereby the chain tensioner acts on the taut section and on the slack section of the chain by means of relatively movable tensioning elements provided at pistons nested one within the other, acted upon with oil from a pressure space and guided in a cylindrical housing.
A chain tensioner with a housing is described in the DE-GM No. 75 22 501 which accommodates two nested pistons. Oil is fed to the piston by way of a collecting pan.
It is the object of the present invention to provide a chain tensioner whose pressure space between the pistons is supplied with oil in a simple but safe manner. In connection therewith, the housing of these pistons is to be provided with means for the easy fastening at an internal combustion engine.
The underlying problems are solved according to the present invention in that the housing includes a fastening eye which extends essentially axially parallel to the housing and is secured at an internal combustion engine housing part by means of a bolt and in that the oil supply to the pressure space of the pistons takes place by way of the bolt and the housing.
The advantages principally achieved with the present invention reside in that the housing together with the fastening eye--and also the extensions--can be manufactured in a simple manner and can be easily fastened at the internal combustion engine housing part by means of the bolt. Therebeyond, the oil supply of the two pistons by way of the bolt is advantageous because separate external lines to the housing can be dispensed with. Additionally, the guidances between the housing and tensioning elements assure that the latter remain fixed in their predetermined position also under high loads.